When talking about the Fulcrums & Levers of the body and the relationship between these and injury prevention as well as performance enhancement, it all begins with the Fulcrum & Lever closest to the ground, the foot and ankle. In the human functional body, the foot is designed to provide stability, while the ankle is designed to provide mobility. Without stability of the foot, the body will attempt to 'compensate' and find the stability somewhere up the bio-mechanical chain in order to push, pull, squat, lunge, twist flex, or extend, whether in the gym or in everyday life. The next link in the chain up the body is the ankle. With an unstable (weak) foot, the ankle will try to take up the slack and may become locked up and function will be decreased. In order to prevent this from occurring, a relatively simple fix is to strengthen/stabilize the foot (fulcrum) so that the ankle can maintain it's mobility. A very common exercise (and well researched) is the "Short Foot" (as developed and popularized by the very famous orthopedic researcher, Vladimir Janda - <link>). Around here at SODO Health & Performance we like to call it "Strong Foot" (sounds more fun!).
The basic premise is to strengthen the 'intrinsic' muscles of the foot, thereby taking the demand off the ankle (and further structures up the bio-mechanical chain of the body). <StrongFoot link> Practicing this daily, in bare feet, can improve the stability of the foot and therefore improve overall function, performance, and decrease the risk of injury.